Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:4.1.1.17 (ornithine decarboxylase)
 6,351 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate receptors (AMPARs) mediate the majority of fast excitation in the CNS. Receptors lacking GluR2 exhibit inward rectification and paired-pulse facilitation (PPF) due to polyamine (PA)-dependent block and unblock, respectively. In this study, we tested whether rectification and PPF in immature, but not mature, pyramidal neurons depend not only on the absence of functional GluR2 but also on the level of endogenous PAs. Whole cell recordings were obtained from layer V pyramidal neurons of P12-P14 or P16-P20 rats in the presence or absence of spermine in the pipette (50 microM). Isolated minimal excitatory synaptic responses were obtained, and paired (20 Hz) stimuli were used to investigate the rectification index (RI) and paired-pulse ratio (PPR). Spermine and its synthetic enzyme, ornithine decarboxylase (ODC), expression was examined using immunostaining and Western blot, respectively. At the immature stage (<P15) inclusion of intracellular spermine increased rectification and PPF for evoked excitatory postsynaptic currents (EPSCs) but had little or no effect on either measure in more mature (P16-P20) pyramidal neurons. Depletion of PAs reduced rectification suggesting that endogenous PAs play a critical role in functional regulation of AMPARs. Spermine immunoreactivity and ODC expression in immature rat neocortex (<P15) were greater than more mature tissue by approximately 20 and 60%, respectively. These results provide further support for the idea that excitatory synapses on immature neocortical pyramidal neurons ubiquitously contain AMPA receptors lacking the GluR2 subunit and that the level of endogenous PAs plays an important role in modulating AMPAR-dependent neurotransmission.
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PMID:Polyamines modulate AMPA receptor-dependent synaptic responses in immature layer v pyramidal neurons. 1584 96

Endophytic isolates of Trichoderma species are being considered as biocontrol agents for diseases of Theobroma cacao (cacao). Gene expression was studied during the interaction between cacao seedlings and four endophytic Trichoderma isolates, T. ovalisporum-DIS 70a, T. hamatum-DIS 219b, T. harzianum-DIS 219f, and Trichoderma sp.-DIS 172ai. Isolates DIS 70a, DIS 219b, and DIS 219f were mycoparasitic on the pathogen Moniliophthora roreri, and DIS 172ai produced metabolites that inhibited growth of M. roreri in culture. ESTs (116) responsive to endophytic colonization of cacao were identified using differential display and their expression analyzed using macroarrays. Nineteen cacao ESTs and 17 Trichoderma ESTs were chosen for real-time quantitative PCR analysis. Seven cacao ESTs were induced during colonization by the Trichoderma isolates. These included putative genes for ornithine decarboxylase (P1), GST-like proteins (P4), zinc finger protein (P13), wound-induced protein (P26), EF-calcium-binding protein (P29), carbohydrate oxidase (P59), and an unknown protein (U4). Two plant ESTs, extensin-like protein (P12) and major intrinsic protein (P31), were repressed due to colonization. The plant gene expression profile was dependent on the Trichoderma isolate colonizing the cacao seedling. The fungal ESTs induced in colonized cacao seedlings also varied with the Trichoderma isolate used. The most highly induced fungal ESTs were putative glucosyl hydrolase family 2 (F3), glucosyl hydrolase family 7 (F7), serine protease (F11), and alcohol oxidase (F19). The pattern of altered gene expression suggests a complex system of genetic cross talk occurs between the cacao tree and Trichoderma isolates during the establishment of the endophytic association.
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PMID:Fungal and plant gene expression during the colonization of cacao seedlings by endophytic isolates of four Trichoderma species. 1683 90